Survival and toxicity differences between 5-day and weekly cisplatin in patients with locally advanced cervical cancer

BACKGROUND. Cisplatin (CDDP) administration concomitant with radiotherapy (RT) for the treatment of locally advanced cervical cancer has evolved from an inpatient 5-day every 21-day regimen to a weekly outpatient regimen. This study was designed to test for differences in progression-free survival (PFS) and toxicity between the 2 regimens. METHODS. In all, 77 consecutive patients at a single institution with stage IB2-IV cervical cancer were included in this analysis (using the International Federation of Gynecologists and Obstetricians staging system). All patients were treated with CDDP, external beam RT, and 2 9-Gy high-dose-rate brachytherapy treatments. Two cohorts were compared: 1) 5-day, patients treated from 1995 to 2001 with CDDP 20 mg/m² x 5 days every 21 days concomitant with RT; 2) weekly, treated after May 2001 with CDDP 40 mg/m² weekly concomitant with RT. RESULTS. In all, 50 patients were treated with the 5-day regimen and 27 patients with the weekly regimen. There were no significant demographic differences between the groups. Overall 3-year PFS, controlling for stage, was 90% and 76% for 5-day and weekly groups, respectively (P = .01). Adjusting for stage, age, and completion of treatment, the risk of treatment failure among the weekly group was 3.46 times higher than the 5-day group (P = .02). The weekly group had a 3.43 times higher risk of developing acute toxicities than the 5-day group (P = .02) in advanced-stage patients. CONCLUSIONS. Patients who received weekly CDDP have a shorter 3-year PFS. Patients with advanced-stage cervical cancer who received weekly CDDP had significantly more acute toxicities. These data should be confirmed in a multiinstitutional, randomized, controlled study.